In the conventional window assembly involving inner and outer trackways with upper and lower window sashes movably mounted thereon the primary difficulty resides in washing the exterior of each window sash from the interior of the building or room. In many cases access to the window exterior must be achieved by working from the outside.
Sometimes the problem has been solved by pivotally mounting the window so that it is capable of swinging upon a vertical axis or a horizontal axis such that the exterior of the window assembly can be disposed upon the interior of a building or room. This does not solve the problem in the general case of double hung conventional windows which are adapted for sliding movements within trackways.